The late David Foster Wallace's unfinished final novel, The Pale King, is set for publication in the UK next year following an intensely contested auction between six British publishers.

Foster Wallace, author of the virtuosic, 1,000-page masterpiece Infinite Jest, killed himself last September following a long depression. His wife discovered piles of a manuscript for the novel Foster Wallace had described as the "Long Thing" in their garage, and detailed structural outlines have subsequently come to light.

"I think it's as good as Infinite Jest. I'm really, really blown away by what I've read," said Simon Prosser, publishing director of Penguin imprint Hamish Hamilton, who won the battle for UK rights. "It's absolutely incredible. The level of writing is so high. It's just so tremendously sad that he didn't realise how close he was to what he wanted to achieve."

Always critical of his own work, Foster Wallace struggled to write The Pale King, corresponding with Jonathan Franzen and Don DeLillo about his worries, telling Franzen that in order to complete it he would have to write "a 5,000 page manuscript and then winnow it by 90%, the very idea of which makes something in me wither and get really

interested in my cuticle, or the angle of the light outside". He compared writing it to "trying to carry a sheet of plywood in a windstorm", his longterm editor Michael Pietsch told the New Yorker.

Set in an Internal Revenue Service tax centre, starring one David Wallace, it focuses on the lives of the IRS employees and how they deal with the boredom of their jobs; he aimed "to be emotionally engaging and to write about boredom while being entertaining and to show the world what it was to be a human being", said Penguin in a statement this morning.

"He actually went to work [at the IRS] for a bit," said Prosser, who described the book as "bold, ambitious, original, moving, funny". "His challenge was to write about something so big you could hardly comprehend it – a world of mind-numbingly boring work. There's an amazing preface in which he talks about how he wants you to read the book ... he tells us that 'the very last thing this book is is some kind of clever metafictional titty-pincher'."

Penguin will publish next spring, said Prosser, who was adamant that although the work is unfinished, nothing would be added to it. "You'll get literally 50 pages of a perfect section, then a note to himself saying 'insert X here'. In a lot of cases, the X exists, but there will be some parts that don't. The challenge will be to remain as true as possible to what is there," he said. "Personally I think that if 'notes to self' are included, it'll be fine. We'll obviously present it as an unfinished novel – he himself thought he hadn't finished it. What's so tragic is that he didn't realise how close he was."

As well as 1996's Infinite Jest, described by DeLillo as a "three-stage rocket to the future", Foster Wallace was the author of another novel, The Broom of the System (1987), and collections of short stories and essays.

"You could smell the ozone from the crackling precision of his sentence structure," Franzen said at a memorial service for the author last October.